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Updated: Aug 26, 2025
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Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
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3D Perovskite (1,5-3.2.2-H2dabcn)CsBr3 with Reverse Symmetry Breaking
Pan Wang1, Mengxia Zhang1, Zhenhong Wei1
1School of Chemistry and Chemical Engineering, Nanchang University, Nanchang 330031, People's Republic of China.
Inorganic Chemistry
|October 5, 2022
Summary
Researchers report a novel three-dimensional hybrid organic-inorganic perovskite, (1,5-3.2.2-H2dabcn)CsBr3. This material exhibits switchable dielectric and second-harmonic generation properties due to an unusual reversible phase transition.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- Hybrid organic-inorganic perovskites (HOIPs) are extensively studied.
- Limited research exists on three-dimensional (3D) alkali metal cesium halide perovskites.
Purpose of the Study:
- To synthesize and characterize a novel 3D HOIP.
- To investigate its structural, dielectric, and second-harmonic generation (SHG) properties.
Main Methods:
- Single-crystal X-ray diffraction
- Phase transition analysis
- Dielectric property measurements
- Second-harmonic generation (SHG) measurements
Main Results:
- A new 3D HOIP, (1,5-3.2.2-H2dabcn)CsBr3, was synthesized.
- The compound exhibits a reversible order-disorder phase transition.
- Switchable dielectric and SHG properties were observed.
- An unusual inverted symmetry breaking occurs during the phase transition (Pmn21 to P2/m).
Conclusions:
- The synthesized 3D HOIP demonstrates promising switchable properties.
- The observed inverted symmetry breaking presents a unique phenomenon in perovskite materials.
- This study expands the scope of 3D HOIPs with potential applications in functional materials.
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